1. 下载oracle的客户端程序包（30M）
      只需要在Oracle下载一个叫Instant Client Package的软件就可以了，这个软件不需要安装，只要解压就可以用了，很方便，就算重装了系统还是可以用的。
      下载地址：http://www.oracle.com/technology/software/tech/oci/instantclient/htdocs/winsoft.html
解压到一个目录中即可，例如c:\oracleclient

2. 配置操作系统环境变量

NLS_LANG=SIMPLIFIED CHINESE_CHINA.ZHS16GBK
TNS_ADMIN=C:\oracleclient

3. 配置连接Oracle的配置。tnsnames.ora文件到目录C:\oracleclient。可以从oracle服务器拷贝一个过来。
内容类似：

# tnsnames.ora Network Configuration File: E:\oracle\product\10.2.0\db_1\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.

ORCLProduct =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = prmpatm1.asiapacific.hpqcorp.net)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl)
    )
  )

ORCL122 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 16.157.133.122)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl)
    )
  )

EXTPROC_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))
    )
    (CONNECT_DATA =
      (SID = PLSExtProc)
      (PRESENTATION = RO)
    )
  )

4. 安装PLSQL Developer

5. 配置PLSQL Developer（第一次可以不用登录直接进到PLSQL Developer）
Tools --> Preferences--> Connections,
Oracle Home内容为 C:\oracleclient
OCI library内容为 C:\oracleclient\oci.dll

重新启动PLSQLDeveloper
完毕